Wind Loads on Tall Buildings: A Comparative Study of the International Wind Codes and Numerical Simulation

Wind codes and standards have been used commonly when designing regularshaped tall buildings to withstand wind loads. High-Frequency Base Balance (HFBB) data analysis and Computational Fluid Dynamics (CFD) have now emerged as alternative techniques to these wind codes and standards. This paper compares wind-induced building responses estimated from CFD analysis and those obtained using major international wind codes: AS/NZS1170.2:2011 (Australia/New Zealand), AIJ-RLB-2004 (Japan) and Eurocode-2005 (Europe), with HFBB predictions. The initial comparison was done on a rectangular 60-storey building model and subsequently, the study was extended to building models with different b/d ratios (breadth/depth) under three height categories. The results show that there are minor discrepancies between the code-predicted alongwind responses and those obtained using different approaches with different b/d ratios. Moreover, the across-wind responses predicted by the wind codes significantly deviate from the HFBB results, especially when the wind direction is normal to the shorter face of the building. The deviations intensify as the b/d ratio decreases. Nevertheless, the CFD predictions correspond well with the HFBB predictions for along-wind responses having deviations under 10%, highlighting the capability of CFD simulation for predicting global wind-induced responses of tall buildings.